Technical Field
The present invention relates to a printing device and printing method.
Related Art
An inkjet printer as a printing device is equipped with a printing head which has nozzle rows formed with a plurality of nozzles for discharging ink aligned in a fixed direction.
As related technology, printing devices are known that print a pseudo band with main scan passes N times (N is a natural number) by moving the printing head in the sub scan direction for each of the main scan passes (see Unexamined Patent Publication No. 2011-235592). With Unexamined Patent Publication No. 2011-235592, the pseudo band is printed by printing odd numbered rows using eight nozzles with the first pass, moving print media in the sub scan direction by half the nozzle pitch, and printing even numbered rows using the same eight nozzles with the second pass.
The density of the ink discharged from each nozzle constituting a nozzle row (ink droplets) is preferably fixed and does not depend on the nozzles. This is because it is easy to visually recognize unevenness (color unevenness, density unevenness) in the printing results when there is a difference in density of the ink discharged for each nozzle. The inventors found out that it is easy for there to be a difference between the density of the ink discharged by nozzles positioned near the end of the nozzle row and the density of ink discharged by nozzles positioned near the center of the nozzle row. Based on this kind of knowledge, taking into consideration prior art such as Unexamined Patent Publication No. 2011-235592, within the pseudo band, an area for which printing is done only by nozzles near the ends, and areas for which printing is done only by nozzles near the center occur, so there remains the possibility of visually recognizing differences in concentration of the printing results between these areas as unevenness.